JP2018035072A - Diazadienyl compound, raw material for forming thin film, and method for producing thin film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diazadienyl compound that is suitable as a raw material for forming a thin film by CVD or ALD, has high vapor pressure, resists spontaneous combustion, and has high thermal decomposition initiation temperature; a raw material for forming a thin film containing the compound; and a method for producing a thin film using the raw material.SOLUTION: A diazadienyl compound is represented by formula (I). [Ris a C1-6 linear or branched alkyl group; M is Ni or Mn].SELECTED DRAWING: None

Description

  The present invention relates to a novel diazadienyl compound, a raw material for forming a thin film containing the compound, and a method for producing a thin film using the raw material for forming a thin film.

  Thin film materials containing metal elements are applied to various applications because they exhibit electrical characteristics, optical characteristics, and the like. For example, nickel and nickel-containing thin films are mainly used for members of electronic parts such as resistance films and barrier films, members for recording media such as magnetic films, and members for thin film solar cells such as electrodes.

  Examples of the method for producing the thin film include a sputtering method, an ion plating method, a MOD method such as a coating pyrolysis method and a sol-gel method, a CVD method, and an atomic layer deposition method (hereinafter sometimes referred to as an ALD method). The CVD method and the ALD method are mainly used because the quality of the obtained thin film is good.

  A large number of various raw materials have been reported as a metal source used in chemical vapor deposition. For example, Patent Document 1 discloses a diazadienyl complex that can be used as a thin film forming raw material by the ALD method. Yes. Patent Document 2 discloses a diazadiene metal compound that can be used in chemical vapor deposition or atomic layer deposition. Patent Document 1 and Patent Document 2 do not specifically describe the diazadiene compound of the present invention.

US Patent Application Publication No. 2013/0164456 Special table 2013-545755 gazette

  When vaporizing raw materials for chemical vapor deposition to form a metal-containing thin film on the substrate surface, chemical vapor deposition that has a high vapor pressure, is not pyrophoric, and can form a high-quality thin film Raw materials for use are preferred. In order to form a high-quality thin film, it is necessary to perform heating at 200 ° C. or higher using the ALD method. Therefore, it can be applied to the ALD method, has a high vapor pressure, and is not pyrophoric. There has been a demand for a raw material for chemical vapor deposition having a thermal decomposition starting temperature of 200 ° C. or higher. The high-quality thin film means that the residual carbon content in the film is small.

  As a result of repeated studies, the present inventors have found that a specific diazadienyl compound can solve the above problems, and have reached the present invention.

  The present invention provides a diazadienyl compound represented by the following general formula (I).

(In the formula, R ¹ represents a linear or branched alkyl group having 1 to 6 carbon atoms, and M represents a nickel atom or a manganese atom.)

  Moreover, this invention provides the raw material for thin film formation containing the diazadienyl compound represented by the said general formula (I).

  Furthermore, the present invention introduces a vapor containing a diazadienyl compound obtained by vaporizing the raw material for forming a thin film into a film forming chamber provided with a substrate, and decomposes and / or chemically reacts the diazadienyl compound. The present invention provides a method for producing a thin film, in which a thin film containing at least one atom selected from nickel atoms and manganese atoms is formed on the surface of the substrate.

  According to the present invention, a diazadienyl compound having a high vapor pressure, no spontaneous ignition, and a very high thermal decomposition starting temperature can be obtained. The diazadienyl compound is particularly suitable as a raw material for forming a thin film by a CVD method or an ALD method. The raw material for forming a thin film containing the diazadienyl compound can form a high-quality thin film with a low residual carbon content in the film by a CVD method or an ALD method. Especially, since the diazadienyl compound of the present invention has a particularly good reactivity with hydrogen, the raw material for forming a thin film containing the diazadienyl compound forms a very high-quality metallic nickel thin film by the ALD method. can do.

FIG. 1 is a schematic view showing an example of an apparatus for chemical vapor deposition used in the method for producing a thin film according to the present invention. FIG. 2 is a schematic diagram showing another example of a chemical vapor deposition apparatus used in the thin film manufacturing method according to the present invention. FIG. 3 is a schematic view showing another example of the chemical vapor deposition apparatus used in the method for producing a thin film according to the present invention. FIG. 4 is a schematic diagram showing another example of a chemical vapor deposition apparatus used in the thin film manufacturing method according to the present invention.

  The diazadienyl compound of the present invention is represented by the above general formula (I), is suitable as a precursor for a thin film production method having a vaporization step such as a CVD method, and forms a thin film using the ALD method. You can also.

In the above general formula (I) of the present invention, R ¹ represents a linear or branched alkyl group having 1 to 6 carbon atoms, and M represents a nickel atom or a manganese atom.

Examples of the linear or branched alkyl group having 1 to 6 carbon atoms represented by R ¹ include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a secondary butyl group, and a tertiary butyl group. Group, pentyl group, isopentyl group, hexyl group and the like.

In the general formula (I), a compound in which R ¹ is a methyl group has a high vapor pressure, a high thermal decomposition starting temperature, and a high-quality thin film when used as a raw material for forming a thin film by a CVD method or an ALD method. Is particularly preferable since it can be obtained. In the case of a method for producing a thin film by the MOD method that does not involve a vaporization step, R ¹ can be appropriately selected depending on the solubility in the solvent used, the thin film formation reaction, and the like.

  Preferable specific examples of the diazadienyl compound represented by the general formula (I) include, for example, the following compound No. 1-No. The compound represented by 12 is mentioned. In addition, the following compound No. 1-No. 12, “Me” represents a methyl group, “Et” represents an ethyl group, “Pr” represents a propyl group, “iPr” represents an isopropyl group, “sBu” represents a secondary butyl group, “ “tBu” represents a tertiary butyl group.

The diazadienyl compound of the present invention is not particularly limited by its production method, and is produced by applying a known reaction. For example, when producing a diazadienyl compound of nickel, for example, an inorganic salt such as nickel halide or nitrate, or a hydrate thereof, and the corresponding diazadiene compound are mixed with sodium, lithium, sodium hydride, sodium amide, water. Method of reacting in the presence of a base such as sodium oxide, sodium methylate, ammonia, amine, etc., inorganic salts such as nickel halides and nitrates or hydrates thereof, sodium complexes, lithium complexes, potassium of the corresponding diazadiene compounds Examples include a method of reacting with a complex or the like.
In addition, the diazadiene compound used here is not specifically limited by the manufacturing method, It can manufacture by applying a well-known reaction. For example, there can be mentioned a method obtained by extracting a reaction product obtained by reacting an alkylamine and an alkylglyoxal in a solvent such as trichloromethane with a suitable solvent and performing a dehydration treatment.

  The thin film forming raw material of the present invention is a thin film precursor made of the diazadienyl compound of the present invention described above, and the form thereof varies depending on the manufacturing process to which the thin film forming raw material is applied. For example, when producing a thin film containing only at least one metal selected from nickel and manganese, the raw material for forming a thin film of the present invention does not contain a metal compound and a semimetal compound other than the diazadienyl compound. On the other hand, in the case of producing a thin film containing two or more kinds of metals and / or metalloids, the raw material for forming a thin film of the present invention is a compound containing a desired metal and / or a metalloid in addition to the diazadienyl compound. (Hereinafter also referred to as other precursors). As will be described later, the thin film forming raw material of the present invention may further contain an organic solvent and / or a nucleophilic reagent. As described above, the raw material for forming a thin film according to the present invention is suitable for CVD and ALD methods because the physical properties of the diazadienyl compound that is a precursor are suitable. ) Is useful.

  In the case where the thin film forming raw material of the present invention is a chemical vapor deposition raw material, the form is appropriately selected depending on the method such as the transporting and supplying method of the CVD method used.

  As the above transportation and supply method, the raw material for CVD is vaporized by heating and / or depressurizing in a container in which the raw material is stored (hereinafter sometimes simply referred to as a raw material container), and is necessary. Gas transport method for introducing a vapor into a film forming chamber (hereinafter also referred to as a deposition reaction part) where a substrate is installed, together with a carrier gas such as argon, nitrogen, helium or the like used accordingly, for CVD There is a liquid transport method in which a raw material is transported to a vaporization chamber in a liquid or solution state, vaporized by being heated and / or decompressed in the vaporization chamber to be vaporized, and the vapor is introduced into a film formation chamber. In the case of the gas transport method, the diazadienyl compound itself represented by the above general formula (I) can be used as a raw material for CVD. In the case of the liquid transport method, the diazadienyl compound itself represented by the above general formula (I) or a solution obtained by dissolving the compound in an organic solvent can be used as a raw material for CVD. These CVD raw materials may further contain other precursors, nucleophilic reagents, and the like.

  In the multi-component CVD method, the CVD raw material is vaporized and supplied independently for each component (hereinafter sometimes referred to as a single source method), and the multi-component raw material is mixed in advance with a desired composition. There is a method of vaporizing and supplying a mixed raw material (hereinafter, sometimes referred to as a cocktail sauce method). In the case of the cocktail sauce method, a mixture of the diazadienyl compound of the present invention and another precursor or a mixed solution obtained by dissolving the mixture in an organic solvent can be used as a raw material for CVD. This mixture or mixed solution may further contain a nucleophilic reagent and the like.

  As said organic solvent, it does not receive a restriction | limiting in particular, A well-known common organic solvent can be used. Examples of the organic solvent include acetates such as ethyl acetate, butyl acetate and methoxyethyl acetate; ethers such as tetrahydrofuran, tetrahydropyran, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, dibutyl ether and dioxane; Ketones such as butyl ketone, methyl isobutyl ketone, ethyl butyl ketone, dipropyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, methylcyclohexanone; hexane, cyclohexane, methylcyclohexane, dimethylcyclohexane, ethylcyclohexane, heptane, octane, toluene, Hydrocarbons such as xylene; 1-cyanopropane, 1-cyanobutane, 1-cyanohexa , Hydrocarbons having a cyano group such as cyanocyclohexane, cyanobenzene, 1,3-dicyanopropane, 1,4-dicyanobutane, 1,6-dicyanohexane, 1,4-dicyanocyclohexane, 1,4-dicyanobenzene Pyridine, lutidine and the like. These organic solvents may be used alone or in combination of two or more depending on the solubility of the solute, the relationship between the use temperature and boiling point, the flash point, and the like. When these organic solvents are used, the total amount of the precursor in the CVD raw material, which is a solution obtained by dissolving the precursor in the organic solvent, is 0.01 to 2.0 mol / liter, particularly 0.05 to 1.0 mol / liter. It is preferable to make it liter. The amount of the entire precursor is the amount of the diazadienyl compound of the present invention when the thin film forming raw material of the present invention does not contain a metal compound and a semimetal compound other than the diazadienyl compound of the present invention. When the forming raw material contains a compound containing another metal and / or a compound containing a metalloid (another precursor) in addition to the diazadienyl compound, this is the total amount of the diazadienyl compound of the present invention and the other precursor.

  In the case of a multi-component CVD method, the other precursor used together with the diazadienyl compound of the present invention is not particularly limited, and a well-known general precursor used as a CVD raw material can be used.

  Other precursors mentioned above include hydrides, hydroxides, halides, azides, alkyls, alkenyls, cycloalkyls, aryls, alkynyls, aminos, dialkylaminoalkyls, monoalkylaminos, dialkylaminos, diamines, di (silyls) -Alkyl) amino, di (alkyl-silyl) amino, disilylamino, alkoxy, alkoxyalkyl, hydrazide, phosphide, nitrile, dialkylaminoalkoxy, alkoxyalkyldialkylamino, siloxy, diketonate, cyclopentadienyl, silyl, pyrazolate, guanidinate, One type selected from the group consisting of phosphoguanidinate, amidinate, ketoiminate, diketiminate, carbonyl and phosphoamidinate as a ligand Compounds of kinds of silicon or metal.

  The precursor metal species include magnesium, calcium, strontium, barium, radium, scandium, yttrium, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, iron, osmium, cobalt, rhodium, iridium, palladium. , Platinum, copper, silver, gold, zinc, cadmium, aluminum, gallium, indium, germanium, tin, lead, antimony, bismuth, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium , Erbium, thulium, ytterbium.

  Other precursors described above are known in the art, and their production methods are also known. As an example of the production method, for example, when an alcohol compound is used as the organic ligand, the inorganic salt of metal or its hydrate described above is reacted with the alkali metal alkoxide of the alcohol compound. Thus, a precursor can be manufactured. Here, examples of the metal inorganic salt or hydrate include metal halides and nitrates, and examples of the alkali metal alkoxide include sodium alkoxide, lithium alkoxide, and potassium alkoxide.

  In the case of the single source method, the above-mentioned other precursor is preferably a compound having similar thermal and / or oxidative decomposition behavior to that of the diazadienyl compound of the present invention, and in the case of the cocktail source method, the heat and / or oxidation. In addition to being similar in decomposition behavior, those that do not undergo alteration due to chemical reaction or the like during mixing are preferred.

  Among the other precursors described above, examples of the precursor containing titanium, zirconium, or hafnium include compounds represented by the following formulas (II-1) to (II-5).

(In the formula, M ¹ represents titanium, zirconium, or hafnium, and R ^a and R ^b are each independently substituted with a halogen atom, and may have an oxygen atom in the chain. R ^c represents an alkyl group having 1 to 8 carbon atoms, R ^d represents an alkylene group having 2 to 18 carbon atoms which may be branched, and R ^e and R ^f each independently represents a hydrogen atom. Or an alkyl group having 1 to 3 carbon atoms, R ^g , R ^h , R ^k and R ^j each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and p represents an integer of 0 to 4 And q represents 0 or 2, r represents an integer of 0 to 3, s represents an integer of 0 to 4, and t represents an integer of 1 to 4.)

In the above formulas (II-1) to (II-5), the alkyl having 1 to 20 carbon atoms which may be substituted with a halogen atom and may contain an oxygen atom in the chain, represented by R ^a and R ^b Groups include methyl, ethyl, propyl, isopropyl, butyl, secondary butyl, tertiary butyl, isobutyl, pentyl, isopentyl, neopentyl, tertiary pentyl, hexyl, and cyclohexyl. Group, 1-methylcyclohexyl group, heptyl group, 3-heptyl group, isoheptyl group, tertiary heptyl group, n-octyl group, isooctyl group, tertiary octyl group, 2-ethylhexyl group, trifluoromethyl group, perfluorohexyl Group, 2-methoxyethyl group, 2-ethoxyethyl group, 2-butoxyethyl group, 2- (2-methoxyethoxy) ethyl group, 1- Toxi-1,1-dimethylmethyl group, 2-methoxy-1,1-dimethylethyl group, 2-ethoxy-1,1-dimethylethyl group, 2-isopropoxy-1,1-dimethylethyl group, 2-butoxy -1,1-dimethylethyl group, 2- (2-methoxyethoxy) -1,1-dimethylethyl group, and the like. The alkyl group having 1 to 8 carbon atoms represented by R ^c, a methyl group, an ethyl group, a propyl group, an isopropyl group, butyl group, secondary butyl group, tertiary butyl group, an isobutyl group, a pentyl group, Isopentyl, neopentyl, tertiary pentyl, hexyl, 1-ethylpentyl, cyclohexyl, 1-methylcyclohexyl, heptyl, isoheptyl, tertiary heptyl, n-octyl, isooctyl, third An octyl group, 2-ethylhexyl group, etc. are mentioned. Further, the branched alkylene group which may having 2 to 18 carbon atoms represented by ^{R d,} a group provided by glycols. Examples of the glycol, for example, 1,2-ethanediol, 1,2 Propanediol, 1,3-propanediol, 1,3-butanediol, 2,4-hexanediol, 2,2-dimethyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 2,2-diethyl-1,3-butanediol, 2-ethyl-2-butyl-1,3-propanediol, 2,4-pentanediol, 2-methyl-1,3-propanediol, 1-methyl- 2,4-pentanediol and the like can be mentioned. Examples of the alkyl group having 1 to 3 carbon atoms represented by R ^e and R ^f include a methyl group, an ethyl group, a propyl group, and a 2-propyl group. Examples of the alkyl group having 1 to 4 carbon atoms represented by R ^g , R ^h , R ^j and R ^k include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a secondary butyl group, and a tertiary butyl group. And isobutyl group.

  Specifically, as a precursor containing titanium, tetrakis (ethoxy) titanium, tetrakis (2-propoxy) titanium, tetrakis (butoxy) titanium, tetrakis (second butoxy) titanium, tetrakis (isobutoxy) titanium, tetrakis (third butoxy) Tetrakisalkoxytitaniums such as titanium, tetrakis (tertiarypentyl) titanium, tetrakis (1-methoxy-2-methyl-2-propoxy) titanium; tetrakis (pentane-2,4-dionato) titanium, (2,6-dimethyl) Tetrakis β-diketonatotitaniums such as heptane-3,5-dionato) titanium, tetrakis (2,2,6,6-tetramethylheptane-3,5-dionato) titanium; bis (methoxy) bis (pentane-2) 4-Dionato) titanium, bis (ethoxy) bis (pentane-2,4-dionato) titanium, bis (tertiarybutoxy) bis (pentane-2,4-dionato) titanium, bis (methoxy) bis (2,6- Dimethylheptane-3,5-dionato) titanium, bis (ethoxy) bis (2,6-dimethylheptane-3,5-dionato) titanium, bis (2-propoxy) bis (2,6-dimethylheptane-3,5 -Dionato) titanium, bis (tert-butoxy) bis (2,6-dimethylheptane-3,5-dionato) titanium, bis (tertiaryamyloxy) bis (2,6-dimethylheptane-3,5-dionato) titanium Bis (methoxy) bis (2,2,6,6-tetramethylheptane-3,5-dionato) titanium, bis (ethoxy) Bis (2,2,6,6-tetramethylheptane-3,5-dionato) titanium, bis (2-propoxy) bis (2,6,6,6-tetramethylheptane-3,5-dionato) titanium, Bis (tertiary butoxy) bis (2,2,6,6-tetramethylheptane-3,5-dionato) titanium, bis (tertiaryamyloxy) bis (2,2,6,6-tetramethylheptane-3, Bis (alkoxy) bis (β-diketonato) titanium, such as 5-dionato) titanium; (2-methylpentanedioxy) bis (2,2,6,6-tetramethylheptane-3,5-dionato) titanium, (2-methylpentanedioxy) bis (2,6-dimethylheptane-3,5-dionato) titanium and other glycoxybis (β-diketonato) titaniums; Lopentadienyl) tris (dimethylamino) titanium, (ethylcyclopentadienyl) tris (dimethylamino) titanium, (cyclopentadienyl) tris (dimethylamino) titanium, (methylcyclopentadienyl) tris (ethylmethylamino) titanium , (Ethylcyclopentadienyl) tris (ethylmethylamino) titanium, (cyclopentadienyl) tris (ethylmethylamino) titanium, (methylcyclopentadienyl) tris (diethylamino) titanium, (ethylcyclopentadienyl) (Cyclopentadienyl) tris (dialkylamino) titanium such as tris (diethylamino) titanium, (cyclopentadienyl) tris (diethylamino) titanium; (cyclopentadienyl) Lis (methoxy) titanium, (methylcyclopentadienyl) tris (methoxy) titanium, (ethylcyclopentadienyl) tris (methoxy) titanium, (propylcyclopentadienyl) tris (methoxy) titanium, (isopropylcyclopentadi (Enyl) tris (methoxy) titanium, (butylcyclopentadienyl) tris (methoxy) titanium, (isobutylcyclopentadienyl) tris (methoxy) titanium, tert-butylcyclopentadienyl) tris (methoxy) titanium, (penta And (cyclopentadienyl) tris (alkoxy) titanium such as methylcyclopentadienyl) tris (methoxy) titanium. Examples of the precursor containing zirconium or the precursor containing hafnium include compounds in which titanium in the compound exemplified as the precursor containing titanium is replaced with zirconium or hafnium.

  Examples of the precursor containing a rare earth element include compounds represented by the following formulas (III-1) to (III-3).

(In the formula, M ² represents a rare earth atom, and R ^a and R ^b each independently represents an alkyl group having 1 to 20 carbon atoms which may be substituted with a halogen atom and may contain an oxygen atom in the chain. R ^c represents an alkyl group having 1 to 8 carbon atoms, R ^e and R ^f each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ^g and R ^j each independently represent A C1-C4 alkyl group is represented, p 'represents the integer of 0-3, r' represents the integer of 0-2.)

In the precursor containing the rare earth element, the rare earth atom represented by M ² includes scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, Examples include ytterbium and lutetium. Examples of the group represented by R ^a , R ^b , R ^c , R ^e , R ^f , R ^g, and R ^j include the groups exemplified for the precursor containing titanium.

  In addition, the raw material for forming a thin film of the present invention may contain a nucleophilic reagent as needed to impart the stability of the diazadienyl compound of the present invention and other precursors. Examples of the nucleophilic reagent include ethylene glycol ethers such as glyme, diglyme, triglyme and tetraglyme, 18-crown-6, dicyclohexyl-18-crown-6, 24-crown-8, dicyclohexyl-24-crown-8. , Crown ethers such as dibenzo-24-crown-8, ethylenediamine, N, N′-tetramethylethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, 1,1,4,7,7- Polyamines such as pentamethyldiethylenetriamine, 1,1,4,7,10,10-hexamethyltriethylenetetramine and triethoxytriethyleneamine, cyclic polyamines such as cyclam and cyclen, pyridine, pyrrolidine and pipette Heterocyclic compounds such as gin, morpholine, N-methylpyrrolidine, N-methylpiperidine, N-methylmorpholine, tetrahydrofuran, tetrahydropyran, 1,4-dioxane, oxazole, thiazole, oxathiolane, methyl acetoacetate, ethyl acetoacetate, Β-ketoesters such as acetoacetate-2-methoxyethyl or β-diketones such as acetylacetone, 2,4-hexanedione, 2,4-heptanedione, 3,5-heptanedione, and dipivaloylmethane It is done. The amount of these nucleophilic reagents used is preferably in the range of 0.1 mol to 10 mol, more preferably 1 to 4 mol, relative to 1 mol of the whole precursor.

  The raw material for forming a thin film according to the present invention contains as little impurities metal elements as possible, impurities halogen such as impurity chlorine, and impurities organic components as much as possible. The impurity metal element content is preferably 100 ppb or less for each element, more preferably 10 ppb or less, and the total amount is preferably 1 ppm or less, more preferably 100 ppb or less. In particular, when used as an LSI gate insulating film, gate film, or barrier layer, it is necessary to reduce the content of alkali metal elements and alkaline earth metal elements that affect the electrical characteristics of the thin film obtained. The impurity halogen content is preferably 100 ppm or less, more preferably 10 ppm or less, and most preferably 1 ppm or less. The impurity organic content is preferably 500 ppm or less in total, more preferably 50 ppm or less, and most preferably 10 ppm or less. In addition, since moisture causes generation of particles in the raw material for chemical vapor deposition and generation of particles during thin film formation, the precursor, organic solvent, and nucleophilic reagent are used to reduce their respective moisture. It is better to remove moisture as much as possible before use. The moisture content of each of the precursor, the organic solvent, and the nucleophilic reagent is preferably 10 ppm or less, and more preferably 1 ppm or less.

  Moreover, it is preferable that the raw material for forming a thin film of the present invention contains particles as little as possible in order to reduce or prevent particle contamination of the formed thin film. Specifically, in the particle measurement by the light scattering liquid particle detector in the liquid phase, the number of particles larger than 0.3 μm is preferably 100 or less in 1 ml of the liquid phase, and larger than 0.2 μm. The number of particles is more preferably 1000 or less in 1 ml of the liquid phase, and the number of particles larger than 0.2 μm is most preferably 100 or less in 1 ml of the liquid phase.

  As a method for producing a thin film of the present invention for producing a thin film using the thin film forming raw material of the present invention, a vapor obtained by vaporizing the thin film forming raw material of the present invention and a reactive gas used as necessary are used as a substrate. The film is introduced into a film forming chamber in which is deposited, and then a precursor is decomposed and / or chemically reacted on the substrate to grow and deposit a metal-containing thin film on the surface of the substrate. There are no particular restrictions on the method of transporting and supplying the raw material, the deposition method, the production conditions, the production apparatus, etc., and well-known general conditions and methods can be used.

  Examples of the reactive gas used as necessary include oxygen, ozone, nitrogen dioxide, nitric oxide, water vapor, hydrogen peroxide, formic acid, acetic acid, acetic anhydride, etc. Examples of reducing substances include hydrogen, and examples of nitrides that can be used include organic amine compounds such as monoalkylamines, dialkylamines, trialkylamines, and alkylenediamines, hydrazine, and ammonia. Can be used alone or in combination of two or more. Among them, the diazadienyl compound of the present invention has a particularly good reactivity with hydrogen, and therefore, when hydrogen is used as a reactive gas, a very high quality metallic nickel thin film can be formed by the ALD method.

  Examples of the transport and supply method include the gas transport method, liquid transport method, single source method, and cocktail sauce method described above.

  In addition, the above deposition methods include thermal CVD in which a raw material gas or a raw material gas and a reactive gas are reacted only by heat to deposit a thin film, plasma CVD using heat and plasma, photo CVD using heat and light, In addition, optical plasma CVD using light and plasma, and ALD in which the deposition reaction of CVD is divided into elementary processes and deposition is performed stepwise at the molecular level.

  Examples of the material of the substrate include silicon; ceramics such as silicon nitride, titanium nitride, tantalum nitride, titanium oxide, titanium nitride, ruthenium oxide, zirconium oxide, hafnium oxide, and lanthanum oxide; glass; metals such as metal ruthenium. . Examples of the shape of the substrate include a plate shape, a spherical shape, a fiber shape, and a scale shape. The substrate surface may be a flat surface or a three-dimensional structure such as a trench structure.

Moreover, as said manufacturing conditions, reaction temperature (base | substrate temperature), reaction pressure, a deposition rate, etc. are mentioned. About reaction temperature, 150 degreeC or more which is the temperature which the diazadienyl compound of this invention fully reacts is preferable, 150 to 400 degreeC is more preferable, and 200 to 350 degreeC is especially preferable. The reaction pressure is preferably atmospheric pressure to 10 Pa in the case of thermal CVD or photo CVD, and preferably 2000 Pa to 10 Pa in the case of using plasma.
The deposition rate can be controlled by the raw material supply conditions (vaporization temperature, vaporization pressure), reaction temperature, and reaction pressure. When the deposition rate is large, the properties of the obtained thin film may be deteriorated. When the deposition rate is small, a problem may be caused in productivity. Therefore, 0.01 to 100 nm / min is preferable, and 1 to 50 nm / min is more preferable. In the case of the ALD method, the number of cycles is controlled so as to obtain a desired film thickness.

  The production conditions further include temperature and pressure when the thin film forming raw material is vaporized into steam. The step of vaporizing the raw material for forming a thin film to form a vapor may be performed in a raw material container or in a vaporization chamber. In any case, the thin film forming raw material of the present invention is preferably evaporated at 0 to 150 ° C. In addition, when the thin film forming raw material is vaporized in the raw material container or in the vaporization chamber to form a vapor, the pressure in the raw material container and the pressure in the vaporization chamber are both preferably 1 to 10,000 Pa.

  The thin film production method of the present invention employs the ALD method, and in addition to the raw material introduction step of vaporizing the thin film forming raw material into vapor by the above transport and supply method, and introducing the vapor into the film forming chamber, A precursor thin film forming step for forming a precursor thin film on the surface of the substrate by the diazadienyl compound in the vapor, an exhausting step for exhausting unreacted diazadienyl compound gas, and the precursor thin film as a reactive gas and a chemistry You may have the metal containing thin film formation process of making it react and forming the thin film containing the said metal on the surface of this base | substrate.

  Below, each said process is demonstrated in detail. When forming a metal thin film containing at least one atom selected from nickel atoms and manganese atoms by the ALD method, first, the raw material introduction step described above is performed. Preferred temperatures and pressures when the thin film forming raw material is steam are the same as those described above. Next, a precursor thin film is formed on the substrate surface by the diazadienyl compound introduced into the deposition reaction part (precursor thin film forming step). At this time, heat may be applied by heating the substrate or heating the deposition reaction part. The precursor thin film formed in this step is a thin film formed by decomposition and / or reaction of a part of the diazadienyl compound and has a composition different from that of the target metal thin film. The substrate temperature when this step is performed is preferably room temperature to 500 ° C, more preferably 150 to 350 ° C. The pressure of the system (in the film forming chamber) when this step is performed is preferably 1 to 10,000 Pa, and more preferably 10 to 1000 Pa.

  Next, unreacted diazadienyl compound gas and by-product gas are exhausted from the deposition reaction part (exhaust process). Ideally, unreacted diazadienyl compound gas or by-produced gas is completely exhausted from the deposition reaction part, but it is not always necessary to exhaust completely. Examples of the exhaust method include a method of purging the system with an inert gas such as nitrogen, helium, and argon, a method of exhausting by reducing the pressure in the system, and a method combining these. When the pressure is reduced, the degree of pressure reduction is preferably 0.01 to 300 Pa, and more preferably 0.01 to 100 Pa.

  Next, a reactive gas is introduced into the deposition reaction section, and the target metal thin film is obtained from the precursor thin film obtained in the precursor thin film formation step by the action of the reactive gas or the action of the reactive gas and heat. Form (metal thin film forming step). The temperature when heat is applied in this step is preferably room temperature to 500 ° C, more preferably 150 to 350 ° C. The pressure of the system (in the film forming chamber) when this step is performed is preferably 1 to 10,000 Pa, and more preferably 10 to 1000 Pa. Since the diazadienyl compound of the present invention has good reactivity with a reactive gas, it is possible to obtain a high-quality metal thin film with a low residual carbon content.

  In the thin film manufacturing method of the present invention, when the ALD method is employed as described above, thin film deposition by a series of operations including the above-described raw material introduction step, precursor thin film formation step, exhaust step, and metal thin film formation step is performed. This cycle may be repeated a plurality of times until a thin film having a required film thickness is obtained. In this case, after performing one cycle, after the unreacted diazadienyl compound gas and the reactive gas and further by-produced gas are exhausted from the deposition reaction part, the next one cycle is performed in the same manner as in the exhaust process. preferable.

  In forming the thin film by the ALD method, energy such as plasma, light, or voltage may be applied, or a catalyst may be used. The timing of applying the energy and the timing of using the catalyst are not particularly limited. For example, when introducing a diazadienyl compound gas in the raw material introduction step, heating in the precursor thin film formation step or thin film formation step, and system in the exhaust step It may be at the time of exhausting inside, at the time of introduction of a reactive gas in the thin film forming step, or between the above steps.

  In the method for producing a thin film of the present invention, after thin film deposition, annealing may be performed in an inert atmosphere, an oxidizing atmosphere, or a reducing atmosphere in order to obtain better electrical characteristics. When embedding is necessary, a reflow process may be provided. The temperature in this case is 200 to 1000 ° C, preferably 250 to 500 ° C.

  As a device for producing a thin film using the raw material for forming a thin film of the present invention, a well-known chemical vapor deposition apparatus can be used. Specific examples of the apparatus include an apparatus capable of supplying a precursor as shown in FIG. 1 and an apparatus having a vaporization chamber as shown in FIG. In addition, as shown in FIGS. 3 and 4, an apparatus capable of performing plasma treatment on a reactive gas can be used. The present invention is not limited to the single wafer type apparatus as shown in FIGS.

  A thin film manufactured using the raw material for forming a thin film of the present invention can be selected from other precursors, reactive gases, and manufacturing conditions as appropriate, so that a desired type of metal, oxide ceramics, nitride ceramics, glass, etc. It can be a thin film. The thin film is known to exhibit various electrical characteristics and optical characteristics, and is applied to various applications. For example, copper and copper-containing thin films are applied as LSI wiring materials because of their high conductivity, high electromigration resistance, and high melting point. Nickel and nickel-containing thin films are mainly used for members of electronic parts such as resistance films and barrier films, members for recording media such as magnetic films, and members for thin film solar cells such as electrodes.

  Hereinafter, the present invention will be described in more detail with examples and evaluation examples. However, the present invention is not limited by the following examples.

[Production Example 1] Production of N, N'-diisopropyl-propane-1,2-diimine A 1 L four-necked flask was charged with 197 g (3.33 mol) of isopropylamine and 496 g (4.16 mol) of dehydrated trichloromethane. Cooled to around 0 ° C. To this solution, 150 g (0.833 mol) of a pyruvaldehyde 40% aqueous solution was added dropwise over 1 hour so that the liquid temperature would be 10 to 14 ° C. After completion of dropping, the mixture was stirred at a liquid temperature of 10 ° C. for 2 hours. Then, the reaction liquid was left still and the organic layer was liquid-separated. Furthermore, the aqueous layer was extracted twice with trichloromethane (100 g) to recover the organic layer. All the organic layers were combined, dehydrated with sodium sulfate, filtered, and then desolvated at an oil bath temperature of 60 to 70 ° C. under slightly reduced pressure. Thereafter, distillation was performed under reduced pressure at an oil bath temperature of 64 ° C. The obtained fraction was a pale yellow transparent liquid, and the yield was 95.5 g and the yield was 74.0%.

(Analysis value)
(1) Mass spectrometry m / z: 154 (M +)
(2) Elemental analysis C: 72.2 mass%, H: 12.0 mass%, N: 17.9 mass% (theoretical value; C: 70.0 mass%, H: 11.8 mass%, N: 18.2% by mass)

Example 1 Compound No. 1 Production of 1 A 1 L four-necked flask was charged with 21.4 g (138.9 mmol) of N, N′-diisopropyl-propane-1,2-diimine obtained above and dehydrated tetrahydrofuran (412 g), and dry ice / IPA It cooled to -30 degreeC with the bath. Into this, 0.988 g (142.4 mmol) of metallic lithium piece was added little by little and reacted at −10 ° C. This solution was added dropwise to a suspension of 9.0 g (69.45 mmol) of nickel chloride and dehydrated tetrahydrofuran (412 g) at around −10 ° C., and the temperature was raised to room temperature and reacted for 15 hours. Thereafter, the solvent was removed at an oil bath temperature of 65 ° C. and slightly reduced pressure. After standing to cool, it was redissolved with dehydrated hexane and filtered through a membrane filter. The obtained filtrate was desolvated under an oil bath temperature of 65 ° C. and slightly reduced pressure, and dried. The obtained residue was distilled at an oil bath temperature of 115 ° C. and 20 Pa to obtain a target product as a red-black viscous liquid. The yield was 5.8 g, and the yield was 20.5%. When the obtained object was left in the atmosphere to check for the presence or absence of spontaneous ignition, there was no spontaneous ignition.

(Analysis value)
(1) ¹ NMR (solvent: heavy benzene) (chemical shift: multiplicity: H number)
(8.976: s: 1) (3.151 to 3.087: m: 1) (2.651 to 2.587: m: 1) (1.937 to 1.870: m: 12) (- 1.408: s: 3)
(2) Elemental analysis (metal analysis: ICP-AES, chlorine analysis: TOX)
Ni: 15.9 mass%, C: 58.6 mass%, H: 10.0 mass%, N: 15.5 mass% (theoretical value; Ni: 16.0 mass%, C: 58.8 mass%) , H: 9.88 mass%, N: 15.3 mass%), chlorine (TOX): less than 10 ppm

[Evaluation Example 1] Evaluation of physical properties of compound About 1 and the following comparative compound 1, the state of each compound in normal pressure 30 degreeC was observed visually. In addition, Compound No. About 1 and the following comparative compound 1, the temperature which thermal decomposition starts was measured using DSC. In addition, Compound No. About 1 and the following comparative compound 1, the temperature when the weight decreased by 50% under reduced pressure was measured using TG-DTA. The results are shown in Table 1.
(Reduced pressure TG-DTA measurement conditions)
10 Torr, Ar flow rate: 50 ml / min, heating rate: 10 ° C./min, sample amount: about 10 mg

  From Table 1 above, Compound No. 1 and Comparative Compound 1 were compounds in a liquid state under the condition of normal pressure of 30 ° C., and both were found to have a thermal decomposition starting temperature of 200 ° C. or higher. Compound No. 1 was found to have a thermal decomposition starting temperature about 15 ° C. higher than that of Comparative Compound 1. In addition, from the results of reduced pressure TG-DTA, Compound No. 1 was found to exhibit sufficient vapor pressure as a raw material for chemical vapor deposition, although the temperature at the time of 50% by mass reduction was slightly higher than that of Comparative Compound 1.

[Example 2] Production of metallic nickel thin film by ALD method 1 was used as a chemical vapor deposition raw material, and a metal nickel thin film was produced on a Cu substrate by the ALD method under the following conditions using the chemical vapor deposition apparatus shown in FIG. About the obtained thin film, when the film thickness measurement by X-ray reflectivity method, the thin film structure and the thin film composition were confirmed by X-ray diffraction method and X-ray photoelectron spectroscopy, the film thickness was 7 to 8 nm. Is metallic nickel (confirmed by Ni2p peak by XPS analysis), and the residual carbon content in the thin film was less than 0.1 atom% which is the lower limit of detection. The film thickness obtained per cycle was about 0.05 nm.

(conditions)
Reaction temperature (substrate temperature): 250 ° C., reactive gas: hydrogen gas (process)
A series of steps consisting of the following (1) to (4) was set as one cycle, and was repeated 150 cycles.
(1) Raw material container heating temperature: 100 ° C., raw material container pressure: 100 Pa Pa The chemical vapor deposition raw material is introduced into the film forming chamber and deposited at a system pressure of 100 Pa for 30 seconds.
(2) Unreacted raw materials and by-product gases are removed by argon purging for 5 seconds.
(3) A reactive gas is introduced into the film forming chamber and reacted at a system pressure of 100 Pa for 30 seconds.
(4) The unreacted raw material and by-product gas are removed by argon purging for 5 seconds.

[Comparative Example 1]
A metallic nickel thin film was produced in the same manner as in Example 2 except that the comparative compound 1 was used as a raw material for chemical vapor deposition. About the obtained thin film, when the film thickness measurement by X-ray reflectivity method, the thin film structure and the thin film composition were confirmed by X-ray diffraction method and X-ray photoelectron spectroscopy, the film thickness was 6 nm, and the film composition was metal. It was nickel (confirmed by Ni2p peak by XPS analysis), and the residual carbon content in the thin film was 24 atom%. The film thickness obtained per cycle was 0.04 nm.

  From the above results, it was found that in Example 2, a metal nickel thin film having a low residual carbon content in the thin film and having a very high quality can be produced by the ALD method. On the other hand, in Comparative Example 1, the presence of a large amount of residual carbon was confirmed in the obtained metallic nickel thin film, and it was found that a metallic nickel thin film with good quality could not be produced.

Claims (4)

The diazadienyl compound represented by the following general formula (I).

(In the formula, R ¹ represents a linear or branched alkyl group having 1 to 6 carbon atoms, and M represents a nickel atom or a manganese atom.) The diazadienyl compound according to claim ¹ , wherein R ¹ in the general formula (I) is a methyl group.   A raw material for forming a thin film comprising the diazadienyl compound according to claim 1 or 2.   A vapor containing a diazadienyl compound obtained by vaporizing the raw material for forming a thin film according to claim 3 is introduced into a film forming chamber in which a substrate is installed, and the diazadienyl compound is decomposed and / or chemically reacted to form the vapor. A method for producing a thin film, wherein a thin film containing at least one atom selected from nickel atoms and manganese atoms is formed on a surface of a substrate.

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